CodeWalrus

Development => Hardware => Topic started by: DarkestEx on October 02, 2016, 10:15:18 pm

Title: Your dream calculator (maybe real sooner than you thought)
Post by: DarkestEx on October 02, 2016, 10:15:18 pm
Hello together.

I have been working on a prototype for a custom calculator. It only has a small, monochrome screen and a convoluted off-the-shelf keypad, but apart from that the hardware is the same as what I might use in a future project. It would be an ST ARMv7M @ 120 MHz with 1024 KB operating system Flash and SD card for program storage. It has 128 KB of RAM and also a coprocessor for WiFi. There is an app available to program it on the go with either your phone, your web browser or with the normal offline development tools you used to love.
What if I said that one could make a calculator out of that?
Would you like the idea?
What screen would you use? What screen technology? OLED, TFT, LCD, maybe even eink?
Also a custom keypad would be used. What layout would you like?


I am curious to what you come up with!
Title: Re: Your dream calculator (maybe real sooner than you thought)
Post by: kotu on October 02, 2016, 10:24:24 pm
remove the wi-fi

wi-fi is weapons tech!!!!

moo  8)
Title: Re: Your dream calculator (maybe real sooner than you thought)
Post by: gameblabla on October 02, 2016, 10:27:01 pm
I would have liked if it had a Dpad on the left and some big buttons.
More RAM would be appreciated because i still think 128kb is too small.

Eink would be very interesting to have on it, i heard they were going to release a multi-color one this year.
If you can't though, OLED would be very nice.
But please, not TFT.

Plus, it would be nice if it's able to generate at least up to 32k colors on-screen.

But i'm not sure if you can do that...
Title: Re: Your dream calculator (maybe real sooner than you thought)
Post by: kotu on October 02, 2016, 10:28:08 pm
pixel shader pipeline
Title: Re: Your dream calculator (maybe real sooner than you thought)
Post by: gameblabla on October 02, 2016, 10:29:45 pm
Quote from: kotu on October 02, 2016, 10:28:08 pm
pixel shader pipeline

you're basically asking him to put a RPI3 inside of a calculator.
That wouldn't be fun if it was so simple to build it :p
Title: Re: Your dream calculator (maybe real sooner than you thought)
Post by: kotu on October 02, 2016, 10:30:45 pm
pixel shader hardware
Title: Re: Your dream calculator (maybe real sooner than you thought)
Post by: DarkestEx on October 02, 2016, 10:42:57 pm
Haha, thanks for the ideas :)

Upgrading RAM is not going to happen. I don't know why 128 KB should not be enough. Especially given that programs are never loaded into RAM to be executed.
WiFi is disabled by default to save power but can be enabled to transfer stuff between your phone / PC and the calculator.

A dpad totally makes sense! I will totally add that :)
Sourcing multi-color or even monochrome einks is hard and I don't think I will go this route.
Even OLEDs are hard to find in sizes that make sense. I will either go for LCD or OLED. TFT is nothing I will consider.

32k colors would take up a lot of memory. I don't really see any use of that tbh ;)
Wouldn't 8 bit color (with palette support) suffice already?
If the screen is high-res this would still eat up a lot of memory. And for a calculator, this would still do fine.
Also think about speed. If updating the screen takes too long, using the calc won't be too much fun.
Title: Re: Your dream calculator (maybe real sooner than you thought)
Post by: xMarminq_ on October 04, 2016, 12:29:50 pm
How about using the WiFi to play the two player games idea I posted.  ;)
Also how about Game-boy emulator support.

How much would it cost too? Estimates?
Title: Re: Your dream calculator (maybe real sooner than you thought)
Post by: DarkestEx on October 04, 2016, 12:55:13 pm
Quote from: xMarminq_ on October 04, 2016, 12:29:50 pm
How about using the WiFi to play the two player games idea I posted.  ;)
Also how about Game-boy emulator support.

How much would it cost too? Estimates?

That would absolutely work. There could be an internet multiplayer or a local one depending on what you prefer.
I am quite certain that emulating the original GameBoy should be possible. I am not sure about the color one though.

I am trying to keep the price around 50-70€.
Title: Re: Your dream calculator (maybe real sooner than you thought)
Post by: xMarminq_ on October 04, 2016, 01:48:49 pm
USD?

EDIT

Did it anyways. 70 to 80 USD.

ANOTHER EDIT :D

Will it do an internet? Like playing browser games, if there is a browser or browser support.
Title: Re: Your dream calculator (maybe real sooner than you thought)
Post by: DarkestEx on October 04, 2016, 02:21:38 pm
Quote from: xMarminq_ on October 04, 2016, 01:48:49 pm
USD?

EDIT

Did it anyways. 70 to 80 USD.

ANOTHER EDIT :D

Will it do an internet? Like playing browser games, if there is a browser or browser support.

Well it depends. I am not yet entirely sure how to make it work in the best way. Also I might change the CPU for good. Is WiFi important for you or not. By removing that one could save some memory and make the device a lot cheaper.

And no, a proper browser would not work with 128 KB RAM.
Title: Re: Your dream calculator (maybe real sooner than you thought)
Post by: xMarminq_ on October 04, 2016, 03:39:08 pm
OK  :'( No diep.io for me...
You could use a micro USB to micro USB for the calculator and scrap the WiFi.  9_9

EDIT

What frame will you use for it? A old calculator frame or one that you will make yourself?
Title: Re: Your dream calculator (maybe real sooner than you thought)
Post by: DarkestEx on October 04, 2016, 08:20:54 pm
Quote from: xMarminq_ on October 04, 2016, 03:39:08 pm
OK  :'( No diep.io for me...
You could use a micro USB to micro USB for the calculator and scrap the WiFi.  9_9

EDIT

What frame will you use for it? A old calculator frame or one that you will make yourself?

There are a few options. In any case, will it be a new case. It would be CNC milled plastic/acryllic or it could be an existing project box that is CNC'd.
Or if you have an idea, let me know.
Title: Re: Your dream calculator (maybe real sooner than you thought)
Post by: p2 on October 04, 2016, 09:06:41 pm
eInk is that stuff those ebook readers use? That stuff is actually really cool... but it makes the use of greyscale impossible... so that's a 100% NOPE!
(maybe add stuff like a few additional loading bars you could use for game stats? like one big screen and aditionally 2 or 4 little bars besides the screen? That would be possible, but I guess it would look stupid lol

a switch for 2 or 3 different clock speeds would be really nice to have ^.^

also wifi is really nice, of cause! But wouldnt nfc or even bluetooth be enough for multiplayer as you got only small amounts of data to transmit? ;)
(But I agree wifi is nice for stuff like IRCs on calcs ^^

also I agree on the RAM point - make it as much as possible ^^
SD cards up to which size will be accepted? :) 4gb? 16gb?
Title: Re: Your dream calculator (maybe real sooner than you thought)
Post by: DarkestEx on October 04, 2016, 09:24:58 pm
Quote from: p2 on October 04, 2016, 09:06:41 pm
eInk is that stuff those ebook readers use? That stuff is actually really cool... but it makes the use of greyscale impossible... so that's a 100% NOPE!
(maybe add stuff like a few additional loading bars you could use for game stats? like one big screen and aditionally 2 or 4 little bars besides the screen? That would be possible, but I guess it would look stupid lol

a switch for 2 or 3 different clock speeds would be really nice to have ^.^

also wifi is really nice, of cause! But wouldnt nfc or even bluetooth be enough for multiplayer as you got only small amounts of data to transmit? ;)
(But I agree wifi is nice for stuff like IRCs on calcs ^^

also I agree on the RAM point - make it as much as possible ^^
SD cards up to which size will be accepted? :) 4gb? 16gb?

RAM is expensive. Like really expensive. 128 KB is really the absolute maximum I could give you. I will not bother with external SRAM and I really don't see a real reason to go for more than 128 KB. Again, this is the pure data memory. No program code is saved there unlike on the TI-84+.

Click speeds will be scaled as needed. User programs will run at the full 120 MHz for speed while the calculator program will run at half or quarter the speed for normal calculations to save battery. For bulk calculations, the clock speed will be restored to 120 MHz (e.g. for graphs).

WiFi is nice. I am almost sure it needs to be there. But I am currently talking to the manufacturer of the WiFi chipset as it might be unavailable in the near future.
NFC is not going to happen for a number of reasons, including the low distance and the low availability (I mean seriously, most phones still don't have it). Bluetooth is not going to happen either. While it is an option if everything fails, WiFi is still a lot more useful and convenient (and cheaper actually). If the WiFi chip I was looking into becomes permanently unavailable, I will go for the ESP8266 as a WiFi coprocessor, but I am hoping that it will not come that far.
Also, who would be meeting in real life anyways? It's not like the 84+ where everybody simply had one. Here you have to go buy something that you like and the next person who has one is probably not your bench neighbor. Over the internet plays sound a lot more reasonable. You can simply turn on your mobile hotspot and let the thing access the internet. It wouldn't be a data hog as there is almost no data sent.
SD cards are accepted up to 32 GB.
Title: Re: Your dream calculator (maybe real sooner than you thought)
Post by: DarkestEx on October 04, 2016, 10:25:55 pm
Important update!

The CPU decision is made!
It will be an Atmel ATSAM4S4A. This is the CPU of the original microcat prototype:
https://www.youtube.com/watch?v=ANFyX-wqNck

The main reason is that I have a lot of these chips still laying around and I have all the test and programming equipment for them. They are also really fast and quite nice little things.
Also, I have already written software for them including a little bootloader and gained experience with them.

The new and final specs are:
128 MHz ARMv7ME CPU. 64 KB RAM. 256 KB Flash memory. 32 GB SD program memory (note that programs are NOT copied to RAM!).
Title: Re: Your dream calculator (maybe real sooner than you thought)
Post by: p2 on October 05, 2016, 08:29:19 am
Looks great  :thumbsup:

But I know I might sound stupid now... but if your cpu runs at 128MHz (compared to the z80 which is at <20MHz) how comes it takes so long to display a text? ^^
Title: Re: Your dream calculator (maybe real sooner than you thought)
Post by: DarkestEx on October 05, 2016, 10:07:38 am
Quote from: p2 on October 05, 2016, 08:29:19 am
Looks great  :thumbsup:

But I know I might sound stupid now... but if your cpu runs at 128MHz (compared to the z80 which is at <20MHz) how comes it takes so long to display a text? ^^

The emulator is not a z80 one but a 6502. The slowness is due to refreshing the screen completely for every character. I have not found time to optimize it yet.
The screen uses 16 bit colors and is 128x128 so it takes time. Also the cpu I running at 8 MHz for testing.
Title: Re: Your dream calculator (maybe real sooner than you thought)
Post by: xMarminq_ on October 05, 2016, 11:20:31 am
What battery will it have? Will it be a lithium ion battery or a double A battery? (-_(//));
Title: Re: Your dream calculator (maybe real sooner than you thought)
Post by: p2 on October 07, 2016, 07:51:28 am
my actual dream calculator would be one running OS-2.43 of the 83+/84+ family but with a GB of ram and archive and variable clock speed ^^

Edit: @DarkestEx you maybe shouldnt post videos showing your IP adress on youtube ^^
Title: Re: Your dream calculator (maybe real sooner than you thought)
Post by: DarkestEx on October 07, 2016, 09:10:24 am
Quote from: p2 on October 07, 2016, 07:51:28 am
Edit: @DarkestEx you maybe shouldnt post videos showing your IP adress on youtube ^^

What do you mean? And where?
Title: Re: Your dream calculator (maybe real sooner than you thought)
Post by: p2 on October 07, 2016, 09:29:25 am
on the bottom of your posts (right size) you can always see your IP adress....
and in the video take a look below the console window you type that DISP HELLO.... ;)
Title: Re: Your dream calculator (maybe real sooner than you thought)
Post by: DarkestEx on October 07, 2016, 10:43:13 am
Quote from: p2 on October 07, 2016, 09:29:25 am
on the bottom of your posts (right size) you can always see your IP adress....
and in the video take a look below the console window you type that DISP HELLO.... ;)

Ah yea. That shouldn't matter a lot. This video is quite old anyways.
Title: Re: Your dream calculator (maybe real sooner than you thought)
Post by: DJ Omnimaga on November 08, 2016, 08:01:40 pm
His IP address probably changed by now or will do so in a few months. In my case, it changes every 4 month maximum and usually changes beforehand. For some people it changes almost daily.

ANyway, I am late as you can see but I am glad this progressed earlier this month and I'm glad to see it in action above :)
Title: Re: Your dream calculator (maybe real sooner than you thought)
Post by: alexgt on November 16, 2016, 03:58:58 am
Nice work @DarkestEx , I like what I see ;).


I have started a Rasp Pi project similar to this, I am hoping to make it at about the same form factor as a ti 84+. It will feature a 480x320 Resistive touch display (I could not find any at that resolution with capacitive touch), a super slimmed down Rasp Pi 3 (completely removing the ethernet port, because of the built-in WiFi and replacing the double USB with single high ones), A full qwerty custom keyboard (with the display beeing directly hooked up to the GPIO pins and not leaving many left I decided to use an Arduino pro mini to multiplex the keyboard to save on GPIO, plans could still change though), and a 3.7v 2000mAh Lipo battery.

My goal with this s to have the portability of a calculator and the power of Pi smashed into one. Also, I could hook it up to any TV in my house and stream games to it from my host PC (don't know how well that would work with the lack of an ethernet port though). This will be a long-term project since I literally have none of the parts or the money to order them :P. And instead of rushing it and not having it just right I want to take m time ad plan everything, I plan on using it sooo... :P
Title: Re: Your dream calculator (maybe real sooner than you thought)
Post by: DJ Omnimaga on December 07, 2016, 05:25:29 am
@alexgt when you have the money and when it starts coming together, you should make a new topic about it. :P

(also I'M late lol)
Title: Re: Your dream calculator (maybe real sooner than you thought)
Post by: DarkestEx on February 03, 2017, 09:14:36 pm
Quote from: alexgt on November 16, 2016, 03:58:58 am
Nice work @DarkestEx , I like what I see ;).


I have started a Rasp Pi project similar to this, I am hoping to make it at about the same form factor as a ti 84+. It will feature a 480x320 Resistive touch display (I could not find any at that resolution with capacitive touch), a super slimmed down Rasp Pi 3 (completely removing the ethernet port, because of the built-in WiFi and replacing the double USB with single high ones), A full qwerty custom keyboard (with the display beeing directly hooked up to the GPIO pins and not leaving many left I decided to use an Arduino pro mini to multiplex the keyboard to save on GPIO, plans could still change though), and a 3.7v 2000mAh Lipo battery.

My goal with this s to have the portability of a calculator and the power of Pi smashed into one. Also, I could hook it up to any TV in my house and stream games to it from my host PC (don't know how well that would work with the lack of an ethernet port though). This will be a long-term project since I literally have none of the parts or the money to order them :P. And instead of rushing it and not having it just right I want to take m time ad plan everything, I plan on using it sooo... :P

Tried a while back. It's a never ending rabbit hole. TLDR: The battery will not fit. We are working on a modified Casio Classpad 300 which fits a Pi3 + TFT shield + battery perfectly fine.
Title: Re: Your dream calculator (maybe real sooner than you thought)
Post by: DJ Omnimaga on February 05, 2017, 08:01:02 pm
Aren't Classpad calcs prohibitively expensive, though? When I tried to build my calculator collection in 2009, the cheapest available ClassPad 300 and 300+ on Ebay were $310 in used condition without the instructions/cable/box... (three times what I paid my Clickpad Nspire with the 84+ keypad)
Title: Re: Your dream calculator (maybe real sooner than you thought)
Post by: DarkestEx on February 05, 2017, 08:44:52 pm
Quote from: DJ Omnimaga on February 05, 2017, 08:01:02 pm
Aren't Classpad calcs prohibitively expensive, though? When I tried to build my calculator collection in 2009, the cheapest available ClassPad 300 and 300+ on Ebay were $310 in used condition without the instructions/cable/box... (three times what I paid my Clickpad Nspire with the 84+ keypad)

Bought a class pad in mint condition. Was fully working. Got it for 30€. However, the internals were all ripped out (except for the keypad PCB which is reused) to make space for the RPi and new Screen.
Title: Re: Your dream calculator (maybe real sooner than you thought)
Post by: alexgt on February 16, 2017, 03:15:16 am
Quote from: DJ Omnimaga on December 07, 2016, 05:25:29 am
@alexgt when you have the money and when it starts coming together, you should make a new topic about it. :P

(also I'M late lol)

I haven't worked on this in a while money, time (FRC Robotics), and school have stopped me...

Quote from: DarkestEx on February 03, 2017, 09:14:36 pm
Quote from: alexgt on November 16, 2016, 03:58:58 am
Nice work @DarkestEx , I like what I see ;).


I have started a Rasp Pi project similar to this, I am hoping to make it at about the same form factor as a ti 84+. It will feature a 480x320 Resistive touch display (I could not find any at that resolution with capacitive touch), a super slimmed down Rasp Pi 3 (completely removing the ethernet port, because of the built-in WiFi and replacing the double USB with single high ones), A full qwerty custom keyboard (with the display beeing directly hooked up to the GPIO pins and not leaving many left I decided to use an Arduino pro mini to multiplex the keyboard to save on GPIO, plans could still change though), and a 3.7v 2000mAh Lipo battery.

My goal with this s to have the portability of a calculator and the power of Pi smashed into one. Also, I could hook it up to any TV in my house and stream games to it from my host PC (don't know how well that would work with the lack of an ethernet port though). This will be a long-term project since I literally have none of the parts or the money to order them :P. And instead of rushing it and not having it just right I want to take m time ad plan everything, I plan on using it sooo... :P

Tried a while back. It's a never ending rabbit hole. TLDR: The battery will not fit. We are working on a modified Casio Classpad 300 which fits a Pi3 + TFT shield + battery perfectly fine.

I planning to 3d print the case so that would solve fitting issues.

Wow, been a while since I posted *.*
Title: Re: Your dream calculator (maybe real sooner than you thought)
Post by: DJ Omnimaga on February 20, 2017, 08:16:29 pm
Quote from: DarkestEx on February 05, 2017, 08:44:52 pm
Quote from: DJ Omnimaga on February 05, 2017, 08:01:02 pm
Aren't Classpad calcs prohibitively expensive, though? When I tried to build my calculator collection in 2009, the cheapest available ClassPad 300 and 300+ on Ebay were $310 in used condition without the instructions/cable/box... (three times what I paid my Clickpad Nspire with the 84+ keypad)

Bought a class pad in mint condition. Was fully working. Got it for 30€. However, the internals were all ripped out (except for the keypad PCB which is reused) to make space for the RPi and new Screen.
Ah I see. Personally I don't like destroying working calcs, but the thing is that the Classpad is so slow to do anything and banned at so many tests that it's not like many people probably want one anymore. Hopefully your project comes to fruition in the future, although if you ever decided to mass produce this calc then you would probably need to replace the Classpad case for public release.
Title: Re: Your dream calculator (maybe real sooner than you thought)
Post by: grosged on February 28, 2017, 10:44:12 pm
Are ClassPad still slow when running asm programs ?
Title: Re: Your dream calculator (maybe real sooner than you thought)
Post by: DJ Omnimaga on March 01, 2017, 11:20:39 pm
They must be much faster. There aren't many of those programs, though, since the calculators were not very popular. It's the BASIC interpreter that was poorly implemented.
Title: Re: Your dream calculator (maybe real sooner than you thought)
Post by: Krillan on March 02, 2017, 02:45:31 am
Some time ago I read from a sh 4 cpu in the cp 400 which runs with about 50 or 60 mhz, switched to the half frequency that it could run.

Quote from: DJ Omnimaga on March 01, 2017, 11:20:39 pm
They must be much faster. There aren't many of those programs, though, since the calculators were not very popular. It's the BASIC interpreter that was poorly implemented.
Title: Re: Your dream calculator (maybe real sooner than you thought)
Post by: Krillan on March 02, 2017, 02:49:15 am
Hm, sorry that I say it, but... getting a cheap thing with a good dsiplay, a cpu with about some 100 mhz cycle and enough ram let's me thin at an older smartphone. Ok, building your own machine is a nice training in hard- and software, ok. But all thights I had about building a tablet with raspberry 3 or anything like this did lead me to used tablets at the bay... sorry about this sacrilegic words...
Title: Re: Your dream calculator (maybe real sooner than you thought)
Post by: c4ooo on March 02, 2017, 03:14:08 am
You should use the edit button to modify your post instead of posting twice in a row ;)
Title: Re: Your dream calculator (maybe real sooner than you thought)
Post by: DJ Omnimaga on March 02, 2017, 04:58:34 am
Quote from: Krillan on March 02, 2017, 02:49:15 am
Hm, sorry that I say it, but... getting a cheap thing with a good dsiplay, a cpu with about some 100 mhz cycle and enough ram let's me thin at an older smartphone. Ok, building your own machine is a nice training in hard- and software, ok. But all thights I had about building a tablet with raspberry 3 or anything like this did lead me to used tablets at the bay... sorry about this sacrilegic words...
I think his goal is to build an actual calculator. :P